


The Experiment

by wolfbunny



Category: Undertale (Video Game)
Genre: Coercion, Dehumanization, Digestion, It's vore, M/M, Nothing but vore, Undertail, Vore, You Have Been Warned, gaster is evil, graphic digestion, just vore, safe vore, seems fatal, semi-willing vore, that should be demonsterization
Language: English
Status: Completed
Published: 2016-11-07
Updated: 2016-11-07
Packaged: 2018-08-29 18:11:02
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings, Graphic Depictions Of Violence
Chapters: 2
Words: 2,040
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/8500045
Author URL: https://archiveofourown.org/users/wolfbunny/pseuds/wolfbunny
Summary: Sans would do anything to keep his brother safe, including:- Get nommed by Asgore





	1. Chapter 1

**Author's Note:**

> Look, an original Undertale vore story!  
> I'm actually working on a longer one, but here's a short one I just thought of.
> 
> UPDATE: Now there is [a picture](http://lycovore.tumblr.com/post/156763417428/collab-with-freaking-squishy-3-there-is-a-story) to go with this :3
> 
> I have made a tumblr just for Undertale vore stuffs:  
> <http://nom-the-skel.tumblr.com>  
> It'll be my UT vore stories, maybe some commentary or status updates, and anything I make or find that has Sans as prey :3

“He’s smiling.”

“That’s just how its face looks.”

“You’re sure … it … doesn’t have any emotions? Even though it has a soul?”

“That was the whole point, sire. No emotions, not even truly sentient. It can’t really do anything but stand there.”

Sans stared straight ahead. Did Asgore really believe this? It took a fair amount of dexterity just to stand upright, not to mention proprioception, and he had actually walked here to the throne room under his own power.

The king studied the skeleton. Sans couldn’t even risk focusing his eyes on the boss monster’s face, but he seemed skeptical.

“I assure you,” Gaster insisted, “it’s not a monster, just a soul container.”

“Hmm,” said the king, frown deepening.

“This is what it was designed for.”

Sans was very careful not to react at all. He needed Asgore to believe Gaster’s story. _If you won’t do it, Papyrus will._

“I suppose I must just get it over with. Is your instrumentation ready, Doctor?”

Gaster must have just nodded, as Sans didn’t hear him answer but the king approached and enclosed his rib cage in a massive paw, lifting him easily.

“It’s trembling.”

“It does that sometimes. It’s just a glitch in the magic holding it together. Please pay it no mind.”

Sans tried to stop shivering, but it wasn’t under voluntary control. Asgore glanced doubtfully at Gaster, but raised the skeleton higher. The king’s big paws made for a comfortable seat, actually, furry against Sans’s bare bones. But the gaping maw that now opened right below his feet was disconcerting to say the least.

Even worse when the king started to lower him into it, his tongue pleasantly warm on the bones of his feet. It was all he could do not to twitch away.

Asgore lowered him further and his feet slid deeper, into the king’s warm wet throat. It was easy enough to get down his legs. Sans couldn’t look down to see the progress, only fixating on the sensations of the king’s mouth around his leg bones. He tried not to think about it—any reaction would reveal Gaster’s deception. And then—well, at that point, Asgore probably wouldn’t believe Gaster if he said he had another skeleton that really _was_ a completely emotionless non-sentient soul container, but surely Gaster would make him regret it.

His pelvis pressed against Asgore’s throat. Would it even fit? The king was huge, but—

The king gulped. So it did fit.

The lower spine was dragged in after it until he felt the king’s jaws surrounding his rib cage. He let his arms dangle limply past Asgore’s lower jaw. A paw was still supporting his head, so he had a great view of the ceiling, but now he was close enough to see a little of Asgore’s nose in his peripheral vision.

The ribs were apparently harder to swallow. This whole situation was a bit hard to swallow, but Sans wouldn’t get a chance to use that joke. After a couple gulps, Asgore used the supporting hand to press against the skeleton’s head, to get him down more quickly. As his rib cage was squeezed tight his head slipped past Asgore’s lips. Goodbye to the ceiling… Hello, reddish blurry thing too close to focus on. Now that Asgore couldn’t see him he took the luxury of darting his eyelights around, but without turning his head he really couldn’t see anything.

Once he had dealt with the ribs and shoulders, it was easy for Asgore to swallow down the skull. Sans let his eyelights gutter out in surrender.

He could feel the cooler air outside on his hands still, even as Asgore slurped up his arms. But soon enough that last contact with the outside world was gone. The powerful muscles of Asgore’s esophagus squeezed him lower, until his feet emerged through a tighter ring into the stomach. Sans had studied enough anatomy to know where he was. Lubricated with saliva and pushed by the inner walls, the rest of him slipped through as well.

Sans tried not to move, to maintain Gaster’s fiction until the end.

_“As you know, most monsters’ souls don’t persist long enough after death to be absorbed. But what if the dying monster was already inside you? If there is even the most minuscule time frame in which to absorb the soul, it should be possible. You might even be able to absorb it before the monster is completely dead.”_

_“Are you saying Asgore is gonna … swallow a monster alive? Like, one who’s about to die anyway?”_

_“That’s what I proposed, but Asgore is … kind to a fault. He doesn’t want to add to the suffering of a dying monster, even a volunteer. But fortunately, we do have some other resources …”_

Sans tensed up as the acids and enzymes began to have an effect on him. It barely stung now, but it was going to get a whole lot worse. It was too late now. The experiment would be completed. It would be best if he just let go, and hopefully lost consciousness sooner rather than later. If the king had been a skeleton too, absorbing food wouldn’t have been such a long, complicated process; he’d have been converted to magic on entry. That might have been preferable. He focused on relaxing each bone in turn, starting with his toes and moving up, willing himself to black out…


	2. Chapter 2

**Notes for the Chapter:**

> If you want Sans to die, just disregard this chapter.  
> If you want Sans to die but *more painfully* only read the first part of this chapter.  
> If you want Sans to live and get a big hug, read the whole thing :3  
> (If you want to skip the pain, skip the first 8 paragraphs and start reading at the triple asterisk ***)
> 
> Congratulations, Sans, you get to be the star of the most graphic and painful digestion scene I have written so far :D Lucky you!

The pain bit into his bones, demanding his attention, not letting him forget what was happening or try to just fall asleep. His feet had it the worst as they had arrived in the stomach first and were at the bottom where the fluids were most concentrated.

He tried to at least hold still, but as it kept getting worse he instinctively tried to jerk his feet away from the source of the pain. It didn’t help at all.

Oh stars, he couldn’t do this. Dying might not be so bad. It wasn’t like he’d had much of a life anyway, cloned by Gaster as an experiment and hidden away in the labs. But if it hurt this much—how could he be in this much pain without just crumbling away to dust? He couldn’t see at all but he knew his feet were still there by the pain.

The worst of it was in his extremities, but it was crawling slowly up his limbs toward his core. He couldn’t help twitching and fidgeting, seeking some escape. Asgore might wonder about it—but Gaster could explain away that much.

He yelped as the burning penetrated deeper into his spine. No—he had to stay quiet. If he’d needed to breathe in order to vocalize this wouldn’t have been a problem, but unfortunately it was all magic. He tried to hold it back but kept emitting a constant whimper as the boss monster’s stomach worked away at him. He squeezed his eyes shut. He could hear voices, Asgore’s voice, and just barely, Gaster. He focused on listening, trying to make them out. It was the only thing he could sense other than the pain.

“—swear I heard something—”

“I’m sure it was just—”

Sans finally blacked out.

***

Sans woke up in the medical center, but it was wrong. The ceiling wasn’t quite the right color. The layout of the room was different.

What had happened? It wasn’t that unusual to wake up with an IV in his arm after one of Gaster’s experiments, but that didn’t explain why he wasn’t in the usual lab. He turned his head to see more of his surroundings. He saw Asgore.

Oh. Right.

Oh! Right! He immediately stopped moving, letting his face fall into a neutral expression—well, a neutral grin anyway—and hoping Asgore hadn’t noticed his surprise. He didn’t dare move his head again, so he kept staring blankly in Asgore’s general direction.

He remembered being—well, he remembered the experiment. What had happened to interrupt it? Was Gaster angry? Was he … going to have to do it again?

“Oh! You’re awake.”

Crap. Asgore had noticed him moving.

“How do you feel, um… Does he have a name?” Asgore looked past him for an answer.

“… Sans.” Gaster’s voice was flat.

Sans didn’t dare move yet. Did that mean the deception was called off? Gaster must be furious … Asgore must be furious with Gaster, too. But right now Asgore was focused entirely on Sans.

“How do you feel, Sans? Please don’t be frightened. I know I may not be the first monster you want to see right now.”

Sans didn’t react at all. What if it was a test? Maybe Asgore didn’t know but just had doubts he wanted assuaged before he went all the way with it.

“You can stop pretending, Sans. I know you’re not just some mindless shell of a monster.”

That was exactly the kind of thing Sans would say if he were in Asgore’s shoes and trying to make him fail the test. He didn’t respond.

The king stood and walked over to kneel by Sans’s bedside. “Sans, it’s okay. I’m not going to … do anything to hurt you. The experiment is canceled.”

That sounded pretty convincing, but … it was also a little too good to be true. One minute he was dying, and in a horrific manner to boot, and the next thing he knew he was in no pain and the king himself was assuring him that everything was okay? He didn’t dare move to see if his hands and feet were still there, but there was no pain, only numbness.

Gaster would be furious if the experiment was canceled. And if Asgore had discovered Gaster was lying about him … there must be consequences for Gaster, too. Sans couldn’t see his creator while he was facing toward Asgore, but he darted his eyelights momentarily toward Gaster.

“You tell him, Doctor Gaster,” instructed the king, “I don’t think he quite believes me.” His voice was the coolest Sans had heard it yet—perhaps he _was_ furious with Gaster.

Sans heard a sigh from behind him. “I appreciate your efforts, Sans, but there’s no point anymore. Just behave normally.”

Sans finally moved to look at Gaster. His expression was irritated but resigned. Still, Sans would just as soon not be left alone with him.

He looked back at the king. First things first. “My brother.”

“You have a brother?” Asgore’s brows lifted in surprise.

“Yes. Gaster …” He glanced back at his creator, who was looking angrier by the moment. Sans had failed at his task, but if Asgore could protect Papyrus from the consequences, it was worth incurring Gaster’s wrath. He managed to sit up. “He told me if I didn’t—my brother would—please don’t let him—”

“It will be okay, Sans. Where is your brother?”

“In the lab … sub-basement …”

“What’s his name?”

“Papyrus.” He leaned against the king’s chest.

“Don’t worry. I won’t let anyone hurt you or Papyrus.” Asgore enveloped the skeleton in a comforting embrace. “Doctor Gaster, my guards will accompany you to fetch Papyrus.” He looked down at Sans again. “Are there any others like you and your brother?”

“No. Just the two of us.”

As the king spoke softly to an attendant whose presence Sans hadn’t even registered, the skeleton turned to look at Gaster from the safety of the king’s arms. The scientist was fuming, but he maintained control, only staring daggers at Sans.

Sans turned back to bury his face in the Asgore’s shirt. He wasn’t wearing armor, and everywhere that wasn’t covered by his clothing was pleasantly fluffy.

The attendant took only a moment to fetch the guards. “Ah, here they are. You’re looking for a skeleton—” He looked down at Sans for confirmation, who nodded. “Named Papyrus, to take into protective custody. Doctor Gaster will guide you. Now don’t take too long. And Doctor, I will decide later what to do with you. It is a shame I can no longer trust you to continue your work with souls. But I will take your cooperation in this matter into consideration.” He disentangled himself from Sans. “Perhaps I should accompany them myself, but I hate to leave you alone after your ordeal, Sans. Can I get you some tea?”

 

**Notes for the Chapter:**

> I didn’t intend for the denouement to be so long. The fun part is over, so then Sans was fine and Asgore pushed Gaster into the core for being a jerk, the end.

**Author's Note:**

> Can monsters actually absorb other monster souls? I'm not sure, but for this story they can :3 I mean, I can think of at least one instance where it happened, but that may have been a special case.


End file.
